The Program project supports an interdisciplinary series of projects on the mechanisms underlying the effects produced by severing afferent or efferent connections to or from neurons of regeneration sprouting and/or reinnervation. The purpose of the programmatic approach are (1) to stimulate interaction and collaboration by investigators from four departments of three institutions, and (2) to support shared facilities at the University of North Carolina. The seven projects are directed at: (a) the relation of behavioral recovery to the regeneration of long-descending tracts after spinal cord section; (b) possible synaptic reorganization in ascending sensory systems after spinal chordotomy; (c) central consequences (neuronal degeneration and death) after peripheral sensory fiber injury; (d) the sensory and efferent consequences of chronic renal denervation and reinnervation; (e) the modifications in effector organ (skeletal muscle and kidney) or sense organ behavior following spinal nerve injury and regeneration; and (f) biochemical changes in spinal motoneurons following injury and regeneration.